diff --git a/srcpkgs/erlang/patches/ERL-490.patch b/srcpkgs/erlang/patches/ERL-490.patch
new file mode 100644
index 00000000000..dbcc98f0c8c
--- /dev/null
+++ b/srcpkgs/erlang/patches/ERL-490.patch
@@ -0,0 +1,101 @@
+From 7715f437ab9a789e0500873b6002a49bfe69009c Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= <bjorn@erlang.org>
+Date: Fri, 29 Sep 2017 07:17:01 +0200
+Subject: [PATCH] Fix incorrect internal consistency failure for binary
+ matching code
+
+4c31fd0b9665 made the merging of match contexts stricter;
+in fact, a little bit too strict.
+
+Two match contexts with different number of slots would
+be downgraded to the 'term' type. The correct way is to
+keep the match context but set the number of slots to the
+lowest number of slots of the two match contexts.
+
+https://bugs.erlang.org/browse/ERL-490
+---
+ lib/compiler/src/beam_validator.erl  |  6 +++---
+ lib/compiler/test/bs_match_SUITE.erl | 38 ++++++++++++++++++++++++++++++++++--
+ 2 files changed, 39 insertions(+), 5 deletions(-)
+
+--- lib/compiler/src/beam_validator.erl
++++ lib/compiler/src/beam_validator.erl
+@@ -1430,13 +1430,13 @@ merge_types(bool, {atom,A}) ->
+     merge_bool(A);
+ merge_types({atom,A}, bool) ->
+     merge_bool(A);
+-merge_types(#ms{id=Id1,valid=B0,slots=Slots},
+-	    #ms{id=Id2,valid=B1,slots=Slots}) ->
++merge_types(#ms{id=Id1,valid=B1,slots=Slots1},
++	    #ms{id=Id2,valid=B2,slots=Slots2}) ->
+     Id = if
+              Id1 =:= Id2 -> Id1;
+              true -> make_ref()
+          end,
+-    #ms{id=Id,valid=B0 band B1,slots=Slots};
++    #ms{id=Id,valid=B1 band B2,slots=min(Slots1, Slots2)};
+ merge_types(T1, T2) when T1 =/= T2 ->
+     %% Too different. All we know is that the type is a 'term'.
+     term.
+diff --git a/lib/compiler/test/bs_match_SUITE.erl b/lib/compiler/test/bs_match_SUITE.erl
+--- lib/compiler/test/bs_match_SUITE.erl
++++ lib/compiler/test/bs_match_SUITE.erl
+@@ -39,7 +39,7 @@
+ 	 match_string_opt/1,select_on_integer/1,
+ 	 map_and_binary/1,unsafe_branch_caching/1,
+ 	 bad_literals/1,good_literals/1,constant_propagation/1,
+-	 parse_xml/1,get_payload/1]).
++	 parse_xml/1,get_payload/1,num_slots_different/1]).
+ 
+ -export([coverage_id/1,coverage_external_ignore/2]).
+ 
+@@ -71,7 +71,7 @@ groups() ->
+        match_string_opt,select_on_integer,
+        map_and_binary,unsafe_branch_caching,
+        bad_literals,good_literals,constant_propagation,parse_xml,
+-       get_payload]}].
++       get_payload,num_slots_different]}].
+ 
+ 
+ init_per_suite(Config) ->
+@@ -1524,6 +1524,40 @@ do_get_payload(ExtHdr) ->
+     <<_:13,_:35>> = ExtHdr#ext_header.ext_hdr_opts,
+     ExtHdrOptions.
+ 
++%% ERL-490
++num_slots_different(_Config) ->
++    Ts = [{<<"de">>, <<"default">>, <<"Remove">>, <<"a">>},
++          {<<"de">>, <<"default">>, <<"Remove from list">>, <<"a">>},
++          {<<"de">>, <<"default">>, <<"Remove from the list">>, <<"a">>},
++          {<<"de">>, <<"default">>, <<"Results">>, <<"Ergebnisse">>},
++          {<<"de">>, <<"default">>, <<"Reservatio">>, <<"a">>},
++          {<<"de">>, <<"navigation">>, <<"Results">>, <<"Ergebnisse">>},
++          {<<"de">>, <<"navigation">>, <<"Resources">>, <<"Ressourcen">>}],
++    _ = [{ok,Res} = lgettext(A, B, C) || {A,B,C,Res} <- Ts],
++
++    {'EXIT',_} = (catch lgettext(<<"d">>, <<"default">>, <<"Remove">>)),
++    {'EXIT',_} = (catch lgettext("", <<"default">>, <<"Remove">>)),
++    {'EXIT',_} = (catch lgettext(<<"de">>, <<"def">>, <<"Remove">>)),
++    {'EXIT',_} = (catch lgettext(<<"de">>, <<"default">>, <<"Res">>)),
++    ok.
++
++
++lgettext(<<"de">>, <<"default">>, <<"Remove">>) ->
++    {ok, <<"a">>};
++lgettext(<<"de">>, <<"default">>, <<"Remove from list">>) ->
++    {ok, <<"a">>};
++lgettext(<<"de">>, <<"default">>, <<"Remove from the list">>) ->
++    {ok, <<"a">>};
++lgettext(<<"de">>, <<"default">>, <<"Results">>) ->
++    {ok, <<"Ergebnisse">>};
++lgettext(<<"de">>, <<"default">>, <<"Reservatio">>) ->
++    {ok, <<"a">>};
++lgettext(<<"de">>, <<"navigation">>, <<"Results">>) ->
++    {ok, <<"Ergebnisse">>};
++lgettext(<<"de">>, <<"navigation">>, <<"Resources">>) ->
++    {ok, <<"Ressourcen">>}.
++
++
+ check(F, R) ->
+     R = F().
+ 
diff --git a/srcpkgs/erlang/template b/srcpkgs/erlang/template
index de27cd87e33..bbd2ae66456 100644
--- a/srcpkgs/erlang/template
+++ b/srcpkgs/erlang/template
@@ -1,7 +1,7 @@
 # Template file for 'erlang'
 pkgname=erlang
 version=20.1
-revision=3
+revision=4
 create_wrksrc=yes
 build_wrksrc=otp_src_${version}
 build_style=gnu-configure